Malleable noncorrodible alloy



Patented May 19, 1925.

UNITED STATES PATENT OFFICE.

WILLIAM H. SIITH, OF CLEVELAND, OHIO, ASSIGNOB TO LUnuUM STEEL 00., O1 WA'IHVLIET, NEW YORK, A CORPORATION OF NEW JERSEY.

IALLEAIBLE NONGORRODIBLE ALLOY.

No Drawing.

To all whom it may concern:

Be it known that I, WILLIAM H. SMITH, a citizen of the United States, residing at Cleveland in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Malleable Noncorrodible Alloys, of which the following is a full, clear, and exact description.

The present invention relates to an alloy which has certain properties both chemical and ph sical which render the alloy exneeding y important from a commercial standpoint, for the manufacture of all artielse or parts of structures wherein the article or structure is subjected to repeated heatings to high temperatures, or where the article or structure is subjected to the action of corrosive liquids, solids or fumes, or to oxidizing gases.

Among thev important properties of the alloy may be mentioned the fact that the alloy is exceedingly resistant to wear and also is resistant to warping, cracking and breaking. Furthermore, the alloy is resistant to corrosion by contact with corroding substances or fumes and is not subject to surface flakin which causes rapid deterioration of an article which exhibits this failing.

A still further desirable property is the fact that the melting point of the alloy is very high, so that an article or part of a structure may be subjected to considerable heat without in any way endangering the structure of the article due to melting or fusing.

The fact that articles and parts of structures made from this alloy do not warp and do not grow, or in other words, increase their dimensions b repeated beatings, makes the alloy excee 'ngly useful in a great many instances.

Among the important uses to which the allo may be put we may mention containers or eat treating boxes, saggars, furnace arts, crucibles, glass molds, metal molds or foundry use, retorts, dies, die rings, and in fact, any structure in the use of which the important roperties of this allo may be utilized. e alloy is also a goo material for the manufacture of electrical resistance elements,- the alloy being non-oxidizing at high temperatures.

One very important use to which the al- Lpplication filed February 27, 1919. Serial No. 278,848.

10y may be put is the making of heat treating boxes, or containers. Boxes made of the proposed alloy are non-warping and nonscahng even though subjected to repeated heating at high temperature and subsequent cooling, and are free from the fault of cracking. Furthermore, the walls of these boxes may be made comparatively thin, thereby lightenin the weight of these boxes to a considerable egree over that necessary where the boxes are made of iron or steel.

The alloy does not materially oxidize when heated or subjected to fumes or gases. The aluminum and silicon at the sur aces of the alloy forms an oxidizing coating or skin which protects the metal from further oxidizing effects.

The alloy comprises as its essential elements, chromium, iron, nickel, and a small proportion of titanium. In addition it is found advantageous to use manganese, as well as silicon and aluminum maybe present if desired, and also a small proportion of carbon.

The alloy may contain 15 to 40 er cent of chromium, 1 to 15 per cent 0 nickel, 3/ 100 of 1 per cent to 10 per cent of titanium, 3/10 of l per cent to 2 per cent of silicon, of 1 per cent to 2 per cent of manganese, and 4/100 of 1 per cent to 2 per cent of aluminum if the presence of aluminum is desired, the balance consisting mainly of iron and carbon. If sulphur and phosphorus be present in the alloy, the amount should be kept as low as possible, preferably less than 5/100 of 1 per cent.

As an example, atypical analysls of an alloy found to contain the desirable qualities, the following is given:

18 per cent chromium, 4 er cent nickel, 1% per cent manganese, 8/1 0 per cent titanium, 1 er cent silicon, 3/100 per cent aluminum i aluminum is present at all, balance iron and carbon.

The chromium is the element which imparts the highly resistant ualities as to wear and corrosion to the a 0y as well as the roperty of non-wa ing. The nickel ren ers the alloy more omogeneous and less likely to cracking when sulnected to repeated hcatings. The manganese gives a good grain to the alloy.

The silicon and aluminum, (if aluminum is used,) are added just before the metal is poured. The silicon acts as a de-oxidizer of the metal bath and also im arts fluidity to the metal so that it is readi y poured.

In the event that the source of ferrochrome used is that of the thermite process, there is likely to be some aluminum in the fiarro-chrome which appears in the final a lo T e titanium performs two functions. While the alloy is in melted condition within the furnace, it acts as a de-oxidizer, part of the titanium combining with occluded ases, particularly nitrogen, and thls comination with titanium is removed by the slag. Additionally, excess of that required as a de-oxidizer, appears in the final alloy and imparts t e properties of toughness, resiliency and resistance to cracking. The quantity of titanium will vary in accordance with the degree in which it is desired to produce the characteristics just mentioned, and may vary within the limits which have before been specified.

The alloy is produced in the electric fur uses by melting ferr0-chrome together with the various other ingredients of the alloy whichhave been mentioned, and with a suitable flux such as is well known in the art. In making the alloy it is only necessary to bring the temperature of the furnace to a suflicient degree to insure a thorough melting and incorporation of the various elements of the .alloy. The final alloy obtained is a metal which is very easily handled in.the foundry and can be poured and cast in manner and by methods similar to those em 10 ed in foundry practice.

The a oy as a high tensile strength, and on fracture shows a fine compact grain. The alloy is tough and resistant to breaka The melting point is high, being in 5i; neighborhood of 2700 Fahrenheit.

It has been found that when the alloy contains a low percentage of carbon, sa .11 per cent to .12 per cent, the alloy is f airly malleable and where the carbon is kept as low as 7/100 per cent to. 8/100 per cent, the alloy 15 also easily machinable. Under many circumstances this qualit of malle ability is important and desirab e.

iHaving described my invention, I claim:

1'. A malleable alloyed soft steel resistant to corrosion and to oxidation containing iron in excess of chromium not less than 15% and not greater than 40%, to-

ther with nickel and titanium not greater t anthe chromium. A

2. A 'malleable alloyed soft steel resistant to corrosion and to oxidation containing iron in excess of 50%, nickel not less than 1% and not greater than 15% together with chromium and titanium not greater than 50% nor less than 15%.

the titanium which is in 3. A malleable alloyed soft steel resistant to corrosion and to oxidation containing iron in excess of 50%, nickel about 515%, titanium not less than .08% nor greater than 10%, together with chromium.

4. A malleable alloyed soft steel resistant to corrosion and to oxidation containing iron in excess of 50%, chromium approximately 18%, nickel not less than 1% nor greater than 15% and a small quantity of titanium.

5. A malleable alloy resistant to corrosion and to oxidation containing as essential ingredients, substantially 15 to 40 per cent of chromium, substantially 1 to 15 per cent of nickel, substantially 3/100 of 1 per cent to 15 per cent of titanium, balance of iron and carbon.

6. A malleable alloy resistant to corrosion and to oxidation consisting of substantially 15% to 40% of chromium, 1% to 15% of nickel, to 2% of manganese, substantially 3/100% to 2 of a metal having the properties of silicon with respect to forming a non-flaking oxide, 2. small quantity of titanium in excess of 3/100%, the balance being iron and carbon.

7. A malleable alloy resistant to corrosion and to oxidation consisting of substantially 18 per cent of chromium, 4 per cent of nickel, 1 per cent of manganese, 8/10% of titanium, balance iron and carbon.

8. Alloyed malleable soft steel resistant to corrosion and to oxidation containin substantially chromium 15% to 40%, nicke 15%, silicon'2.5%, manganese 2%, and titanium about .08%.

9. Alloyed malleable soft steel resistant to common and to oxidation containin substantially chromium 15% to 40%, nicke 15%, materlal having the properties of silicon and aluminum 53% to 4.5%, and titanium about .08%.

10. Alloyed malleable soft steel resistant to corrosion and to oxidation containing substantially chromium 15% to 40%, nickel 1% to 15%, silicon 2.5%, manganese 2%, and titanium about .08%.

11. Alloyed malleable soft steel resistant to corrosion and to oxidation containing substantially chromium 15% to 40%, nicke 1% to 15%, material having the properties of silicon and aluminum .53% to 4.5%, and titanium about .08%.

12. Alloyed malleable soft steel resistant to corrosion and to oxidation containing substantially chromium 15% to 40%, nicke 15%, silicon 2.5%, manganese 2%, and titanium .03% to 10%. T

13. Alloyed malleable soft steel resistant to corrosion and to oxidation containi substantially chromium 15% to 40%, nicke 15%, material having the properties of silicon and aluminum .53% to 4.5%, and tit nium .0370 to 10%.

14. Alloyed malleable soft steelnresistant to corrosion and to oxidation containing substantially chromium 15% to 40%, nickel 1% to 15%, silicon 2.5%, manganese 2%,

5 and titanium 03% to 10%.

15. Alloyed malleabl soft steel resistant to corrosion and to oxidation containing substantially chromium 15% to 40%, nickel 1% to 15%, material having the properties of silicon and aluminum .53% to 4.5%, and 10 titanium .03% to 10%.

In testimony whereof, I

my signature.

hereunto afiix WILLIAM H. SMITH.

14. Alloyed malleable soft steel.resistant substantially chromium 15% to 40%, nickel to OOIIOSIOII and to oxidation containing 1% to 15%, material having the properties substantially chromium 15% to 40%, nickel of silicon and aluminum 53% to 4.5%, and 10 1% to 15%, silicon 2.5%, manganese 2%, titanium .03% to 10%. 5 and titanium .03% to 10%. In testimony whereof, I hereunto aflix 15. Alloyed malleable soft steel resistant my signature. to corrosion and to oxidation containing WILLIAM H. SMITH.

Certificate or Correction.

It is hereby certified that in Letters Patent/No. 1,538,360, granted May 19, 1925, upon the application of William H. Smith, of Cleveland, Ohio, for an improvement in Malleable Noncorrodible Alloys, errors appear in the punted specification requiring correction as follows: Page 1, line 66, before the word fumes insert the word omieiizing, and line 68 for oxidizing read coating; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 30th day of June, A. D. 1925.

[emu] KARL FENNING,

Acting Ouwwnissiamr of Piltemts.

Certificate oI Gorrection.

It is hereby certified that in Letters Patent No. 1,538,360, granted May 19, 1925, upon the application of William H. Smith, of Cleveland, Ohio, for an improvement in Malleable Noncorrodible Alloys, errors appear in the painted specification requiring correction as follows: Page 1, line 66, before the word fumes insert the word oxidizing, and line 68 for oxidizing read coating; and that the said Letters Patent should he read with these corrections therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 30th day of June, A. D. 1925.

[emu] KARL FENNING,

Acting Commissioner of Patents. 

